Resilient tread.



P. W. PRATT.

RESILIENT TREAD.

APPLICATION FILED JULY 16, 1912.

Patented Feb. 17, 1914.

UIETHZED STATES PATENT OFFICE.

PHILIP W. PRATT, OF BOSTON, MASSACHUSETTS.

RESILIENT TREAD.

To all "M/(Ollt it may concern:

Be it: known that I, PHILIP W. Payer, a citizen of the United States, residing at Boston, in the C( unity of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Resilient Treads, of which the following is a specification.

This invention relates to resilient treads, particularly in the shape of elastic tires for vehicle wheels.

The object of the invention is to provide an elastic tread'l'iaving relatively inelastic inserts or [)lllgS, of non-slipping character, the plugs being so arranged that they are operative for the purposes for which they are intended during the entire life of the elastic tread, without detracting materially from the resilience of the tread.

The invention is embodied in a resilient tread comprising a body of elastic material having a tread face which may be the outer surface of an elastic vehicle tire, and a back face which may be the inner surface of the tire bearing on the rigid rim of the wheel, a series of antislipping outer plugs extending inwardly from the tread. face, said plugs being inclined relatively to the tread face, for a purpose hereinafter explained.

Of the accompanying drawings, forming a part of this specification, Figure 1 represents a perspective sectional view of a portion of an elastic tire embodying my invention. Fig. 2 represents a longitudinal section of a portion of an elastic tire constituting another embodiment of the invention.

In the drawings, 12 represents an elastic body which may be composed of any of the compositions of which. .so-called solid rubber tires are usually made. In the outer or tread face of the body 12 are inserted a series of angular or V-shaped plugs, the outer ends 13 of which are flush with the said tread face. then the body 12 is worn away Specification of Letters Patent.

Application filed July 16, 1912.

to swing inwardly hen Patented Feb. 17, 1914-.

Serial No. 709,648.

rubber of the body 12 and plugs 14 causes-a I firm and intimate union between the body' and the plugs and between the convolutions of the fabric of which the plugs are composed. The outer ends of the plugs form parts of the tread surface of the body 12, and not only resist wear of said tread surface, but also reduce liability of slipping or ski dd in g1 The plugs are inclined relatively to the tread surface, instead of being at right angles therewith, as shown in the drawing. This inclination ofthe plugs enables them to swing ormove sidewise inwardly when the surrouiuling portions of the body 12 are compressed, so that the plugs, which are relatively incompressible and unyielding, are displaced side *ise by inward pressure. on the tread surface. and do not detract materially from the resilience of the body.

The inclination of the plug relatively to the tread face not only increases the resiliency of the tread. the plug being adapted the tread face is pressed inwardly, but also provides a greater area of noirslipping surface. in other words, the end of the cylindrical plug when beveled becomes elliptical instead of circular and presents a greater area than the end formed at right angles with the axis of the plug.

In relatively heavy tires there may be two or more rows of plugs, and the plugs of one .row may have an opposite inclination to the plugs of the other row or rows, as shown by Fig. 2, where the plugs of one row are shown by full lines, and the plugs of an adjacent row by dotted lines.

I claim A resllient tread tor tires comprising a body of elastic material "are having a trcau and a series of antrslipping outer pings errculm. in body and tread facat and inclined. relatively thereto,

whereby an 'viderl, eacl'Oll of vulcanized t iagether, said plugs ner portions which are inclined relatively to 60pm: of this patent may be abtaine section vulcanized in said tending imvardly from the said 1 the tread face and to the outer PQILLLQXIS of I the plugs.

i In testimony whereof I have afiixed my signature, in presence of two Witnesses.

g PHILIP \V. PRATT.

l V fitnesses l FORREST R. RONKTONE,

| P. 'W. PEZZETII.

having ind for five cents each, hy addressing the Commissioner of I'atents.

Washington, I). G. 

